A/B testing

A/B Testing Calculator

Differentiate between random noise and real results while running A/B tests up to 80% faster thanks to the AGILE statistical method. Advanced significance calculator for A/B & MVT tests with flexible data monitoring with robust control of false positives and false negatives.

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Maximize the ROI of your A/B tests

  • 20-80% faster testing through flexible sequential analysis (stop early for efficacy or lack of positive effect)
  • Statistical significance & confidence interval calculator with robust false positive and false negative error control
  • Analyze binomial and continuous metrics alike
  • The calculator fully supports A/B and A/B/N tests
  • Tests with optimal business returns using our ROI-optimal planner
  • Automate data reporting and analysis through our APIs
  • Ideal for online experiments in Conversion Rate Optimization (CRO), Landing Page Optimization, Email Marketing, and PPC.

What sets the A/B test calculator apart

Test duration improvement by using AGILE

Much faster A/B tests

Run tests 20-80% faster than traditional best-practice methods, without sacrificing the rigorous statistical error control. This results in benefiting from winners earlier and cutting short losers as quickly as possible. The overall effect is an increase in the business returns of your A/B testing program. Real-life data show an average benefit of 26% for clients of Analytics Toolkit.

The above is all possible thanks to the AGILE statistical method pioneered in the industry by the author of this calculator, Georgi Georgiev.

Evaluate data as it gathers

Achieve flexibility and efficiency with your A/B tests by periodically performing significance tests on the data while avoiding unaccounted for peeking. This is accomplished by special stopping boundaries for efficacy and futility which guide you when to call a test a winner or to cut a non-promising test short.

With this A/B test significance calculator there is no longer the need to compromise between running a proper test and pleasing a client or HiPPo who demands to act on the results right this minute.

Early stopping of an experiment for efficacy
Statistical error guarantees

Calculations you can trust

The unrivaled statistical rigor of this A/B test calculator means you can trust your results are statistically validated. P-values, confidence intervals, and lift estimates are adjusted so they account for testing multiple variants, for periodical evaluation of the data, and other applicable complications.

The tool is embedded in our A/B testing hub making planning and analyzing tests a seamless experience which helps you avoid many of the common pitfalls encountered in applying statistics in A/B testing. Diagnostic tests such as SRM checks are performed automatically to alert you of unforeseen issues. All of this results in trustworthy test results.

Detailed help information

Accessible but exact language with generously sprinkled inline help references and detailed explanations makes navigating the statistical jargon as easy as it can be. Graphical displays of all statistical results help avoid widespread misunderstandings and ensure the correct conclusions are drawn from the statistics.

Experienced CRO professionals and web analysts will appreciate the fairly detailed documentation and explanations accompanying each input and output, giving them the necessary understanding of the underlying machinery and assumptions involved.

Confidence interval graph example
Test data sources

Easily input your test data

There are three ways to get data into this statistical calculator. First, you can manually enter summary data. A tedious process for sure, even with file uploads, but it comes with the benefit that it can be used with any testing system.

The second data input method supported by our statistical significance calculator is to use our simple Data API. It can work with any system for storing A/B test data, including custom-built ones, as long as you have the capability to code the API endpoint. It is nicely complitmented by our powerful Reporting API.

Third, if your AB testing delivery software syncs data to MixPanel® our calculator can automatically extract it using the MixPanel® API. This happens in a completely automated fashion, and you will get email notifications when a test is ready to be stopped.

A/B testing tools

Take your A/B testing to the next level

Experience the power and utility of our A/B testing hub and all tools during our 14-day free trial. No credit card required.

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See what our clients have to say

A tool with real value if you know how to use it. Might seem intimidating at the beginning, but it tries to provide flexibility, accuracy and optimization in your statistical analysis instead of over-simplification.

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Arnau Vendrell
Co-Founder, iSocialWeb Marketing

At Cro Metrics, we've run tens of thousands of experiments for leading brands. Analytics Toolkit and the AGILE test calculator represent a step above and beyond every one of the other tools we've used.

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Ryan Lucht
Director of Strategy, Cro Metrics